Digital Light Procession (DLP in short) projectors generally utilize one to two color wheels to project light with required color onto digital micro-mirror devices (DMD in short). A color wheel generally consists of several colors, and light can passes through only one color region of the color wheel every moment. According to differences in design, the order and duration in which light passes through each color region are different from each other. However, in a same design, the order and respective time period in which light passes through each color region are constant. For example, if it takes a color wheel 10 s (the actual time is much shorter than 10 s, and this value is merely provided as an example here) to make a round, an order in which light passes through the color wheel can be designed as a following order: light successively passes through a red light region, a green light region and a blue light region, wherein the time required for light to pass through the red light region is 5 s, pass through the green light region is 3 s and pass through the blue light region is 2 s.